HID: i2c-hid: Unfollow the panel on shutdown

i2c_hid_core_shutdown() sends SET_POWER(SLEEP) even for panel followers,
but nothing in device_shutdown() guarantees whether the panel, and hence
our own power, is still on by the time we get there.

Do what i2c_hid_core_remove() does and just unfollow the panel.
drm_panel_remove_follower() calls panel_unpreparing() only while the
panel is still prepared, which powers us down properly; if it is already
unprepared no transfer is attempted at all. On MT8196 the panel is
unprepared long before us, so this also drops the ~2s i2c bus timeout
from every reboot.

Fixes: 96a37bfd232a ("HID: i2c-hid: Support being a panel follower")
Suggested-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Justin Yeh <justin.yeh@mediatek.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Jiri Kosina <jkosina@suse.com>

0 files changed, 0 insertions, 0 deletions